Table 3.
Predictive values of the algorithms
| Algorithm | Records Identified | Flare cases | Documentation of gout | ||
|---|---|---|---|---|---|
| n | n | PPV% (95% CI) | n | PPV% (95% CI) | |
| Medication | |||||
|
| |||||
| ICD-9 + medication claim for any gout-related medications* | 503 | 268 | 53.3 (48.9, 57.7) | 498 | 99.0 (98.1, 99.9)) |
|
| |||||
| ICD-9 + medication claim for colchicine | 302 | 163 | 54.0 (48.4, 59.6) | 300 | 99.3 (98.3, 100) |
|
| |||||
| ICD-9 + medication claim for NSAID/cox-2 selective inhibitor | 174 | 87 | 50.0 (42.6, 57.4) | 173 | 99.4 (98.3, 100) |
|
| |||||
| ICD-9 + medication claim for glucocorticoids | 270 | 145 | 53.7 (47.8, 59.7) | 266 | 98.5 (97.0, 100) |
|
| |||||
| Outpatient | |||||
|
| |||||
| ICD-9 + medication claim for any gout-related medications* | 75 | 42 | 56.0 (44.8, 67.2) | 74 | 99.0 (96.8, 100)) |
|
| |||||
| Procedure | |||||
|
| |||||
| ICD-9 + CPT or J code within 7 days | 290 | 172 | 59.3 (53.7, 65.0) | 287 | 99.0 (97.9, 100) |
|
| |||||
| ICD-9 + CPT or J code on same day | 196 | 134 | 68.4 (61.9, 74.9) | 194 | 99.0 (97.6, 100) |
|
| |||||
| Negative Predictive | |||||
| Records Identified | Flare cases | Documentation of gout | |||
| n | n | NPV % (95% CI) | n | PPV% (95% CI) | |
|
| |||||
| ICD-9 + NO medication claim for any gout-related medications* | 200 | 29 | 85.2 (80.2, 90.2) | 196 | 98.0 (96.1, 100) |
95% CI= 95% confidence interval, ICD-9=International Classification of Diseases, 9th Revision; CPT= Current Procedural Terminology; PPV= Positive Predictive Value.
*
gout-related medications include colchicine, NSAIDs, cox-2 selective inhibitor, and glucocorticoids.